Frequently Asked Questions
- How can an Enercon Drilled Venturi Condensate Removal unit be more efficient, more economical, and permanent in comparison to conventional mechanical steam traps – it sounds like the proverbial “magic bullet”?
- We’ve heard that an orifice unit can not handle varying loads – Is that true?
- What are the anticipated financial and performance results in a complete facility conversion from mechanical traps to Enercon orifice units?
- What if there is a first rate maintenance program – what is the advantage of the Enercon drilled venture orifice solution?
- In what type of applications do the Enercon assemblies efficiently operate?
- How can an Enercon Drilled Venturi Condensate Removal unit be more efficient, more economical, and permanent in comparison to conventional mechanical steam traps – it sounds like the proverbial “magic bullet”?
The job of any condensate removal device is to keep steam in the system and get rid of condensate that forms continuously as steam gives up its latent heat and condenses. Water in a steam system reduces heat transfer and causes erosion, corrosion and water hammer. It is critical to purge it quickly and efficiently.
On day one, a properly sized Enercon orifice is more efficient than a brand new mechanical trap - Every condensate removal device, be it an Enercon Drilled Venturi or a mechanical trap has an orifice. Whereas the Enercon device extracts condensate through a non-moving, continual flow device, a mechanical trap operates on a batch system - they open in the presence of condensate and close in the presence of steam. Whether the open/shut mechanism in a mechanical trap is activated by internal floats, buckets, bimetals, bellows or discs, a properly sized Enercon orifice operates continuously operates in the lower end of a Steam Loss to Percentage Condensate Capacity chart while a mechanical trap ramps up into the upper ranges every time it opens. Therefore, in normal operating steam processes, an Enercon unit is usually 3% to 5% more efficient than a perfectly operating mechanical trap.
This superior performance only increases as the mechanical trap begins to wear out. On 24-hour-a-day applications, mechanical traps cycle several times a minute or a couple of million times a year, resulting in wear and leakage. Though mechanical traps average about a 3-5 year lifetime before total failure, the wear and tear from the repeating purge cycle results in the initiation of performance degradation long before that. Due to this degradation and totally failed traps, it is not unusual for the entire mechanical trap population of a plant to be operating at 15% to 25% below its maximum efficiency. On the other hand, since the Enercon Drilled Venturi Condensate Removal unit has no moving parts, it doesn’t wear out and the efficiency experienced in year ten will be exactly the same as that experienced on day one.
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- We’ve heard that an orifice unit can not handle varying loads – Is that true?
With Enercon’s Drilled Venturi Condensate Removal unit, steam traveling at the speed of sound continuously forces much slower condensate (about 30 mph) through a precisely sized hole, blocking steam from escaping. The Enercon unit is sized to handle 100% of the condensate load produced by a particular application. At 100% capacity, an accurately sized orifice device loses no steam and backs up no condensate. Every condensate load varies somewhat and there is a common perception that when the load drops below 100% capacity, orifice devices lose inordinate amounts of steam.
Actually, the opposite is true. When the load drops below 100% capacity, the orifice passes a violently turbulent mixture of equivalent volumes of steam and water, a well-known phenomenon called two-phase flow. Since condensate is several hundred times denser than steam, steam loss is negligible.
For instance, in a 100-psi system producing 375 lbs/hr condensate, an accurately sized Enercon unit loses 1.76 lbs/hr steam if load drops to 25% of capacity, which it will do only sporadically. On the other hand, at 100 psi, a failed mechanical trap with a 1/8” internal orifice loses 52.8 lbs/hr. according to D.O.E. and trap company ‘Leaking Steam Trap Discharge Rate’ charts.
We recommend our units for applications where the load may drop as low as 25% of capacity, although sources such as the U.S. Naval Facilities Engineering Command Supplements (10-90 & 1-92) say ‘a fixed orifice sized for a 100% load operates efficiently down to a 10% load.’
Hampton Affiliates, a leading lumber company which converted seven mills to the Enercon system in 2003 and 2004 says: "Our operations are all zone control, so we have a constant variable load situation. (Enercon) traps perform with excellence in this type of environment."
(Timber Processing magazine July/Aug. 2004)
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- What are the anticipated financial and performance results in a complete facility conversion from mechanical traps to Enercon orifice units?
What are the results? Historically, our customers typically report 10%-25% fuel savings, virtual elimination of steam trap maintenance plus a solution to operational problems such as low and inconsistent temperatures, trap-related pressure drops, high back pressure and water hammer. (See reference letters and linkup to magazine articles in the web site).
What does that mean in terms of fuel savings? As the price of fuel has dramatically increased over the past several years (from $1.60/mcf to over $7.00 or more /mcf for gas users), the savings from a more efficient steam system have also increased dramatically.
For example, at $7/mcf; a facility that runs 100,000 lbs per hour of steam through its 500 unit trapped system and has a typical inefficiency rate of 15% (due to failed and/or mal-functioning mechanical steam traps); the annual fuel savings calculate to $893,000. Taking into account the fuel savings alone, that’s a simple payback of a less than 3 months on a complete conversion to the Enercon units. Reduced maintenance costs and improved operational results only increase this economic benefit.
The actual savings a facility may experience is affected by many factors in addition to the price of fuel and its trap maintenance program. These include such items as the average steam pressure; is it superheated; percentage of the system that is inside versus outside, the amount of a system that is trapped, whether condensate is vented or returned, etc. To determine the anticipated results for a specific facility, we have developed a short questionnaire from which we can calculate the estimated fuel savings.
What about maintenance savings? The country's largest, privately-owned plater eliminated a 30% trap failure rate, cutting annual trap maintenance costs on its 600-trap, 35 psi steam system by $20,000 (President & CEO Magazine Article, Nov/Dec 2001).
A major petrochemical customer calculated the monthly cost of maintaining conventional steam traps in one of its plants (500 traps, 150-psi), in the following chart:
Trap check
(16 hrs. @ $31.00/hr.) |
$496 |
Repair 20 trap failures
(4 hrs. per trap @ $31.00/hr.) |
$2,480 |
| Parts costs: $100 per trap |
$2,000 |
| Monthly trap maintenance |
$4,976 |
| Annual trap maintenance |
$59,712 |
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- What if there is a first rate maintenance program – what is the advantage of the Enercon drilled venture orifice solution?
TO ACHIEVE LESS THAN A 5% TRAP FAILURE RATE, monthly to quarterly mechanical trap inspections are recommended for 100-psi systems, says The Department of Energy (Energy Tips - 6-99). For high pressure systems (150 psi and above), weekly to monthly inspections are recommended. So testing a 1,000-trap, 150 psi system every week/month will hold annual steam losses to less than $150,000 (not including losses from leaking but operational traps). Most production and maintenance people tell us this level of testing is unrealistic, that traps are a low priority, changed on an ‘as need’ basis. They have to concentrate on the more critical projects.
Mechanical Traps Leak. ‘Even for companies with annual test-and-replace programs,’ reports Textile World (February ’02), ‘studies show the average trap has been leaking for six months before it is replaced.’
ENERCON UNITS ARE PERMANENT. Enercon units in plants converted as long as 15 years ago have not needed a replacement or lost any measurable condensate removal efficiency.
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- In what type of applications do the Enercon assemblies efficiently operate? Thousands of Enercon assemblies are operating efficiently on tracing lines, unit heaters, humidifiers, drip legs, submerged coils, heat exchangers, jacketed coils and other applications. On completely converted plants, Enercon has replaced, on average, 99% of existing conventional traps.
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